Automatic switch.



F. A. LUNDQUIST.

AUTOMATIC SWITCH- APPLICATION FILED Dec. 2. 1916.

1,238,164. Patented Aug. 28, 1917.

gl/ 0.2 E/OZ UNITED STATES PATENT OFFICE.

FRANK A. LUNDQUIS'I, OF NEW YORK, N. Y., ASSIGNOR TO WESTERN ELECTRICCOM- PANY, INCORPORATED, 013 NEW YORK, N. Y., A CORPORATION OF NEW YORK.

AUTOMATIC SWITCH.

Application filed December 2, 1916.

To all whom it may concern:

Be it known that I, FRANK A. LUNDQUIST, a citizen of the United States,residing at New York, in the county of New York and State of New York,have invented certain new and useful Improvements in Automatic Switches,of which the following is a full, clear, concise, and exact description.

This invention relates to automatic switches, and particularly toautomatic telephone exchange switches of the panel type.

The object of this invention is to provide means in an automatic switchfor mechanically selecting idle. trunks and thereby eliminating thestep-by-step movement commonly employed for this purpose.

In the present embodiment of this inven tion several groups of terminalsare placed one over the other and a brush carriage is suspended on atape so that in response to a series of impulses the brushes descend tothe desired group, whereupon an idle trunk in that group is seized bythe brushes being stopped in their downward movement by engaging theterminals of the idle trunk. More specifically, the brushes, in responseto the first impulse transmitted, are first displaced so that they willdrop between the terminals of the bank, and then the brushes are allowedto drop a distance of one group for each impulse transmitted. After thelast impulse, the brushes are stopped in their downward movement and aremoved back into a position to engage the terminals of an idle trunk inthe selected group. Then the brushes continue their downward move mentuntil they are stopped by coming into engagement with the terminals ofan idle trunk. A circuit for a magnet is then closed to displace thebrushes and the terminal strip of the selected trunk, which is slidablymounted in the terminal bank to prevent other brushes from engaging themultiple terminals of the selected trunk. Upon the release of theswitch, the terminal strip is first moved back into its normal positionand then the brushes are withdrawn from the terminals before they startupward to their normal positions so that they do not wipe over any ofthe terminals in their up ward movement.

Specification of Letters Patent.

Patented Aug. 28, 1917.

Serial No. 134,575.

Referring to the drawings, Figure 1 is a side elevation of the switchwith a circuit for operating the same; Fig. 2 is a section on the line2-2 of Fig. 1; Fig. 3 is a section on the line 8-3 of Fig. 1; Fig. 1 isa partial view of a modification of the invention; and Fig. 5 is asection on the line 55 of Fig. 1.

In the drawings, 1 represents a frame to which a channel-shaped member 2is pivotally mounted, this channel-shaped member 2 being normally heldagainst a stop 1.7 by spring 16, one end of which is fastened to thearmature 15 fastened to the channel 2, and the other end fastened toextension 97 of the frame 1. A brush carriage 3 is slidably mounted inthe member 2. The brushes 4 and 5 are insulatively mounted on a rod 6',which is slidably mounted in the brush carriage 3. The lever 7 pivotallymounted on the brush carriage serves to move the brushes 4 and 5 out ofengagement with the terminals of the terminal bank 18 in a man nerhereinafter described. The lever 9 is also pivotally mounted on thebrush carriage 3 and serves to control the operation of the lever 7.

One end of the tape 10 is fastened to the lever 9, and the other end ofthe tape is fastened to a drum 19 which is loosely mounted on aconstantly revolving shaft 20. The tape 10 is provided with suitableholes 12, with which the teeth 1% of a wheel 13 engage. A slotted member99 is arranged to assure that the tape 10 will always engage with theteeth of the wheel 13. The wheel 13 and the brush carriage 8 are held intheir normal positions by a dog 21 engaging the catch 22 on the wheel13.

Brushes at and 5 are arranged to engage the terminals 90 and 91 of thebank 18. These terminals are divided into groups one above the other,each group containing terminals of trunks leading to equivalentswitches.

Fig. 3 shows the construction of the bank. Each trunk is connected totwo metal strips insulatively mounted in the bank 18. These strips havea plurality of terminals so that they may be seized by a plurality ofswitches which have access to this terminal bank. A magnet 67 becomesenergized as soon as the and 33.

trunk is seized and by attracting its armature it moves the stripslongitudinally, thereby movingthe terminals of the strips out of thepath of the brushes of other switches.

t is believed that the invention will be best understood by describingthe operation of the switch.

WVhen a subscriber removes his receiver from the hool: his line may beconnected in any well-known manner to the conductors A circuit is thenclosed from ground, battery, relay 34, conductor 33, through thesubscribers substation apparatus, conductor 32, relay 35, to ground. Therelay 35 closes at its inner armature and front contact a circuit fromground, battery, inner armature and front contact of relay 35, conductor37, magnet 36, to ground. The magnet 36 by attracting its armature,allows the holding pawl 38 pivoted at a to engage one of the upper teeth49 of the rack 26.

\Vhen the subscriber transmits a set of impulses to operate the switchshown, relay 34 becomes deenergized each time the line circuit isopened, and closes the circuit for magnet 31. Slow relay 35 is arrangedto keep its armatures attracted during the transmission of the impulses.The circuit of relay 31 is from ground, battery, armature and backcontact of relay 34, conductor 39, outer armature and front contact ofrelay 35, conductor 40, spring 41 and its normal contact, conductor 42,magnet 31, to ground. Magnet 31 is energized each time the line circuitis opened, and by the attraction of its armature 30 the rack 26 is movedthe distance of one tooth by the pawl 29.

Let us assume that two impulses are sent, the rack 26 will then move tothe right a distance of two teeth and is held in this position by thepawl 38. Upon the first ener gization of magnet 31, the dog 21 is movedout of engagement with the catch 22; the wheel 13 is then rotated by thetape 10 being pulled downwardly by the brush carriage 3. The attractionof armature 30 closes the circuit for slow-release magnet 43 fromground, battery, contact 44, spring 45, conductor 46, spring 47 in itsnormal contact, conductor 48, slow-release magnet 43, to ground. Themagnet 43 by attracting its armature closes a locking circuit for itselffrom grounded. battery, contact 44, spring 45, conductor 46, innerarmature and front contact of magnet winding of magnet 43, to ground.Magnet 43, by attracting its middle armature holds the pawl 21 out ofengagement with the catch 22 by means of the cord 64. Magnet 43 byattracting its armature 15 rotates the channel-shaped member 2 with thebrush carriage 3 to displace the brushes 4 and 5 so that they may dropdown between the terminals without engaging any of them.

gages an arm 23 to rotate the shaft 24.

Secured to the shaft 24 is a pinion 60, which meshes with the rack 25 tomove it longitudinally along the pins 61 and 62. Each time an arm isengaged by the catch 22, the rack 25 is moved to the right a distance ofone tooth 50 of the rack 26.

The circumference of the wheel 13 is equal to the distance between thetop of one group of terminals to the top of the next group of terminals.

top. V hen the catch 22 engages an arm 23 for the second time, rack 25will have been moved to the right far enough to engage theend of therack 26 which is prevented from moving to the right by the pawl 51.Since the rack 25 cannot move any farther to the right, further rotationof the wheel 13 is prevented. The rack 25 is prevented from moving tothe left by means of the friction wheel 69 and the spring 70.

The brushes 4 and 5 will now be at the top of the second group. A pin 66is provided on the wheel 13 at a certain distance from the catch 22 sothat when the catch 22 is in engagement with an arm 23, the pin 66 willbe in engagement with the spring 53 and return the spring to its normalposition. Therefore, when the wheel stops with the catch 22 inengagement with arm 23, the holding circuit for magnet 43 is opened atcontact 55 and spring 54. Magnet 43 becomes deenergized and by releasingits armature 15, the channel member 2 is rotated back to its normalposition against the stop 17, thereby positioning the brushes to engageterminals of the idle trunks in the second group. At its inner armatureand back contact magnet 43 closes a circuit for magnet 31, from ground,battery, inner armature and back contact of the magnet 43, conductor100, spring 53, conductor 101, spring 41 in its alternate position(which was closed as soon as the brush carriage 3 left its normalvertical position), conductor 42, magnet 31, to ground. Magnet 31 againattracts its armature 30 and moves the rack 26 a distance of anothertooth to the right. The rack 25 is thereby also allowed to move to theright so that the brush carriage 3, tape 10 and wheel 13 are released.Since the magnet 43 is now deenergized the brushes 4 and 5 are in aposition to engage the terminals of the idle trunk in the group. As soonas engagement is made to the terminals of an idle trunk the downwardmove- Therefore, in the case we have assumed, the brushes 4 and 5 are toengage an idle trunk in the second group from thement of the brushes isstopped. A circuit is then closed for the magnet 67 individual to theseized trunk, the circuit being as fol lows: from ground, battery,magnet 67, conductor 68, terminal 90, brush 4., conductor 33, throughthe substation apparatus, con ductor 32, relay 35, to ground. Magnet 67becomes energized and moves the terminal strips 90 and 91 a distancesuflicient to allow the brushes of other switches to pass by Withoutengaging the terminals of this selected trunk. The brush 5 has a clown-Wardly projecting portion which is engaged by the edge of the lug 90;thus the brushes 4, 5 are carried along with the strips 90, 91.

Connection is now completed from the calling subscriber to an idle trunkleading to another switch and the connection to the called party may nowbe completed in any well-known manner.

The restoring of the switch shown. is as follows: When the callingsubscriber hangs up his receiver the circuit for magnet 67 and relay 35is opened, causing this magnet to become deenergized. Magnet 67 releasesthe terminal strips which are then drawn back into their normal positionby the spring 102. The relay 35 upon becoming deenergized opens'at itsinner armature and front contact the circuit for magnet 36. The magnet36 by releasing its armature withdraws the holding pawl 38. The racks 26and 25 are thereby returned to their normal positions by the spring 52,which was placed under tension by the movement of the rack 26 to theright. The retraction of the armature of magnet 36 releases pin Z) ofthe lever 70 from engagement with said pawl. The spring 71 then is freeto cause said lever to move the drum 19 into engagement with the clutch72 on the revolving shaft 20. The tape 10 is then wound up on the drumwhich returns the wheel 13, the brush carriage 3 and the brushes 4 and 5to their normal positions. As the tape starts upward the lever 9 iswithdrawn from the pin 75 of the lever 7. Spring 8 then rotates thelever 7 until it engages the stop 76. This movement of the lever movesthe brushes 4- and 5 out from the terminals so that as they are movedupward they will not engage any of the terminals during their returnmovement. When the tape 10 reaches its normal position a lug 77 fastenedthereto engages the lever 70 and causes pin 0 to rengage with theshoulder on the lever (Z of the pawl of magnet36. Spring 78 is then freeto move the drum 19 out of engagement with the clutch 7 2. The pin 11fastened to the frame moves the lever 7 into a position whereby thelever 9 engages the pin 75 as soon as the normal position of the switchis reached.

Fig. 4 shows a modification of the switch for use in a three Wiresystem. The test brush 80 and two line brushes 81 and 82 are provided.The test brush 80 is insulatively connected to the brush carriage 3 andthe line brushes 81 and 82 are insulatively connected to an auxiliarybrush carriage 84,

which is fastened to the brush carriage 3 minal of an idle trunk, thetest terminals thereof are moved out of the path of the brushes of otherswitches. The lugs of the strip 119 for this purpose have slots engagedby a tooth e in test brush 80, whereby, when the strip is slid endwise,it carries the carrier 3 and member 2 with it. This results in thebrushes 81, 82 engaging the line terminals 120, 121.

hat is claimed is:

1. In an automatic switch, a plurality of groups of terminals arrangedone above another, a set of gravity operated brushes normally held atthe top of said plurality of groups of terminals, means for allowingsaid brushes to drop to a selected group of terminals, and means fordisplacing said brushes during said group selecting movement to allowsaid brushes to move downward without engaging any of said termi nals.

2. In an automatic switch, a plurality of groups of terminals arrangedone above another, a set of gravity operated brushes normally held atthe top of said plurality of groups of terminals and in a position toengage idle terminals of said groups when allowed to drop directlydownward, means for allowing said brushes to drop to a selected group ofterminals, means for displacing said brushes during said group selectingmovement to allow said brushes to move downward without engaging any ofsaid terminals, means operated when said brushes reach the selectedgroup for releasing said second mentioned means so that said brushes arestopped in their downward movement by engaging the terminals of an idletrunk in the selected group.

3. In an automatic switch, a plurality of groups of terminals arrangedone above an other, a set of gravity operated brushes normally held atthe top of said plurality of groups of terminals and in a position toengage idle terminals of said groups when allowed to drop directlydownward, means for allowing said brushes to drop to a selected group ofterminals, means for displacing said brushes during said group selectingmovement to allow said brushes to move downward without engaging any ofsaid terminals, means operated when said brushes reach the selectedgroup for releasing said second mentioned means to allow said brushes toengage the terminals of an idle trunk in the selected group, andmechanical means for stopping said downward movement of the brushes whensaid brushes engage the terminals of an idle trunk in the selectedgroup.

4. In an automatic switch, a plurality of groups of terminals arrangedone above another, a set of gravity operated brushes normally held atthe top of said plurality of groups of terminals and in a positiontoengage idle terminals of said groups when allowed to drop directlydownward, means for allowing said brushes to drop to a selected group ofterminals, means for displacing said brushes during said group selectingmovement to allow said brushes to move downward without engaging any ofsaid terminals, means operated when said brushes reach the selectedgroup for releasing said second mentioned means so that said brushes arestopped in their downward movement by engaging the terminals of an idletrunk in the selected group, and electromagnetic means operated whensaid brushes engage the terminals of the selected trunk forlongitudinally displacing said terminals out of the path of movement ofsubsequently operated brushes.

5. In an automatic switch, a plurality of groups of terminals arrangedone above another, a set of gravity operated brushes normally held atthe top of said plurality of groups of terminals and in a position toengage idle terminals of said groups when allowed to drop directlydownward, means for allowing said brushes to drop to a selected group ofterminals, means for displacing said brushes during said group selectingmovement to allow said brushes to move downward without engaging any ofsaid terminals, means operated when said brushes reach the selectedgroup for releasing said second mentioned means so that said brushes arestopped in their downward movement by engaging the terminals of an idletrunk in the selected group, a magnet individual to the terminals of theselected trunk for displacing said terminals out of the path of movementof subsequently operated brushes, and a circuit for said magnet closedwhen the terminals of said trunk are engaged by said brushes.

6. In an automatic switch, a plurality of groups of terminals arrangedone above another, a set of gravity operated brushes normally held atthe top of said plurality of groups of terminals, means for allowingsaid brushes to drop to a selected group of terminals, a magnet fordisplacing said brushes during said group selecting movement to allowsaid brushes to move downward without engaging any of the terminals, acircuit for said magnet, and means for opening said circuit when saidbrushes reach the selected group.

7. In an automatic switch, a plurality of groups of terminals arrangedone above another, a set of gravity operated brushes normally held atthe top of said plurality of groups of terminals, means for allowingsaid brushes to drop to a selected group of terminals, means fordisplacing said brushes during said group selecting movement to allowsaid brushes to move downward without engaging any of said terminals,means for allowing said brushes to engage terminals of an idle trunk inthe selected group, means for moving said brushes and the terminals ofsaid selected trunk out of the path of movement of subsequently operatedbrushes, and means operated upon the release of said switch forwithdrawing said brushes from said terminals to allow the brushes to bereturned to their normal position without engaging any of the terminals.

8. In an automatic switch, a plurality of groups of terminals arrangedone above another, a set of gravity operated brushes normally held atthe top of said plurality of groups of terminals, means for allowingsaid brushes to drop to a selected group of terminals, means fordisplacing said brushes a certain amount in one direction during saidgroup selecting movement to allow said brushes to move downward withoutengaging any of the terminals, means for allowing said brushes to engageterminals of an idle trunk in the selected group, means for againdisplacing said brushes and said terminals in said first mentioneddirection, and means operated upon the release of said switch fordisplacing said brushes in a different direction to allow them to bereturned to their normal position without engaging any of the terminals.

9. In an automatic switch, the combination with a plurality of metallicstrips having projecting contact lugs, a frame wherein said strips arelongitudinally movable and so arranged that the lugs of the variousstrips form vertical rows when in their normal positions, a brush foreach row at the top thereof, means for releasing the same, a magnetactuated when said brush engages one of said lugs for moving the stripto which it belongs longitudinally, thus removing the remaining lugsthereon from the path of the other brushes, and means for maintainingthe actuated brush in contact with said lug.

10. In an automatic switch, the combination with a plurality of endwisemovable metallic strips having projecting lugs, means for mounting saidstrips so that the lugs of the various strips form vertical rows when intheir normal position, a brush for each row, means for releasing thesame, a magnet actuated When said brush engages one of said lugs fordisplacing the strip to which it belongs endWise, thus removing theremaining lugs thereon from the path of other brushes, and means carriedby the displaced strip for carrying the actuated brush with it. 10

In Witness whereof, I hereunto subscribe my name this 29th day ofNovember, A. D.,

FRANK A. LUNDQUIST.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, I). G.

